A record of three days of having sex with her sister from morning to night while she was away on a business trip

"Who do you like, sister or me?" I and my girlfriend promised to get married and traveled back and forth between each other's rooms. I thought that those happy days would last forever...until that day... As soon as she left the house on a business trip, I was actively seduced by my sister, and despite feeling guilty, I ended up fucking her with my younger sister, who was more sexy and cuter than her, until I ran out of sperm. The days of having sex with my younger sister were the most lewdest and most vulgar and most exciting in my life, were three days away from her.